Quick release needle clamp

ABSTRACT

A quick release sewing needle clamp that insures proper indexing and easy insertion and removal of a needle is disclosed. The clamp utilizes a hollow needle-bar, a sleeve having a tapered indent, and a spring loaded plunger having a wedge shaped tip. The wedge shaped tip of the spring loaded plunger cooperates with the tapered indent of the sleeve providing a clamping action between the spring loaded plunger and a rear wall of a needle shank receiving slot cut in the needle-bar. The clamping action is released by pressure applied to the spring loaded plunger.

United States Patent Roger I I 1151 63,658,022 14 1 Apr. 25, 1972 1541 QUICK RELEASE NEEDLE CLAMP [72] Inventor: J. Ross Roger, Roselle, NJ. 7

[73] Assignee: The SingerCompany, New-York, NY. [22] Filed: Nov. 19, 1970 [21] App1.No.: 90,974

1521 u.s.c1 ..112/22 FOREIGN PATENTS OR APPLICATIONS France Primary Examiner-James R. Boler Attamey-Marshall J. Breen, Chester A. Williams, Jr. and

Martin Sachs s7 1 ABSTRACT A quick release sewing needle clamp that insures proper in- 1 dexing and easy insertion and removal of a needle'is disclosed.

The clamp utilizes a hollow needle-bar, a sleeve having a tapered indent,vand a spring loaded plunger having a'wedge shaped tip, The wedge shaped tip of the spring loaded plunger cooperates with the tapered indent of the sleeve providing a clamping action between the spring loaded plunger andva rear wall of a needle shank receiving slot cut in the need1e-bar. The clamping action is released by pressure applied to the spring loaded plunger. 1

9 Claims, 4 Drawing Figures 1/1926 Germany ..112/226 FATENTEBAPRES m2 3,658,022

, INVENTOR. Roger J. Ross ATTORNEY WITNESS BACKGROUND OF THE INVENTION Inserting or removing a needle from a prior art needle bar requires that both hands be utilized in a confined area and that the needle be held in position until the screw clamp is tightened.

The preferred embodiment of the present inventions overcomes the short comings of the prior art by providing remote activation of the needle release function with a push-button.

The'push-button also permits immediate retention of the nee- I dle upon release of a spring bias. Maximum visibility of the work area is insured since a needle clamp screw is no longer required.

SUMMARY OF THE INVENTION A preferred embodiment of the present invention provides an improved needle clamp which secures the needle to the needle-bar, is economical to manufacture, is quick to operate, is remotely activated, requires a minimum of effort, and indexes the sewing needle in the needle-bar in the proper sewing position.

A quick release clamping means for securing a sewing machine needle in the free extremity of an endwise reciprocatory sewing machine needle bar, utilizing the principles of the present invention comprises, a needle accommodating seat in the free extremity of the needle bar including a needle locating surface extending substantially parallel to the path of endwise reciprocation of the needle bar, a plunger formed with a needle engaging head, means constraining the plunger for movement relatively to the needle bar substantially parallel to the path of endwise reciprocation thereof and with the needle engaging head disposed opposite the needle locating surface,

and cooperatively associated camming means on the needle bar and on the plunger urging the needle engaging head toward the needle locating surface upon movement of the plunger in one direction along the needle bar and away from the needle locating surface upon movement of the plunger in the other direction along the needle bar.

The clamping means further includes spring means acting between the needle bar and the plunger biasing the plunger in the one direction along the needle bar, and means accessible to a sewing machine operator for shifting the plunger relatively to said needle bar in a direction opposite to the bias of said spring means.

A complete understanding of the invention may be obtained from the following detailed description, when taken in conjunction with the accompanying drawings in which:

DESCRIPTION OF THE DRAWINGS FIG. I is an elevational side view, partially cut away, of a typical sewing machine head including a needle-bar equipped with the quick release needle clamp of the present invention;

FIG. 2 is an exploded perspective view of one embodiment of the needle clamp of the present invention;

FIG. 3 is an enlarged perspective view with a quarter section removed of the preferred embodiment of the quick release needle clamp and a needle shank; and

FIG. 4 is an enlarged sectional view of the lower portion of the needle-bar and sleeve with a needle shank inserted in position taken substantially along line 44 of FIG.

2 DESCRIPTIONlOF THE PREFERRED EMBODIMENT Referring now to the drawings, and more specifically, to FIG. 1, wherein similar reference numerals identify corresponding parts throughout the several views, 10 represents a quick release needle clamp assembly.

A typical sewing machine head 12 has joumaled therein a presser-foot bar 14 and a needle bar 16, positioned above a work supporting surface 18. A cylindrically shaped sleeve 20 is retained by a needle shank engaging roll pin 21, which provides a portion of a needle accommodating seat, to the lower reduced section 22 of needle bar 16. A conventional sewing needle 24 having a shank portion 26 is inserted in aperture 27 of the sleeve 20 to a depth determined by the roll pin 21 and is retained by the quick release needle clamp 10.

Further included in a typical machine head 12 are conven tional components such as a supporting bracket 30, a bushing 32 which is fixed in the sewing head 12 by a set screw 34 and into which is joumaled the presser foot bar 14. Above the bushing 32 and within the hollow sewing head 12 a collar 36 is secured by a set screw 37 to the presser bar 14. The collar 36 is formed with a radially extending tang 38, embraced in a slot not shown, formed in the sewing head 12 to prevent turning of the presser bar. The under side of tang 38 cooperates with a pin 40 carried by presser lifting lever 42 which is fulcrummed on a shouldered screw 44 secured in the sewing head 12 and elevates the presser foot for removal and replacement of work therebeneath.

Further conventional cooperating components include a pressure regulating member 46 joumaled to bracket 30 by a shouldered pivot stud 48, a gate 50 joumaled to link member 52 with the aid of pivot bar 54 and set screw 56 also contains a bearing 57 utilized by the needle-bar 16. Gate 50 is provided with a pivot point .by pivot member 53 which is secured to head 12. The needle-bar jogging machine mechanism 55 is attached to the needle bar and transfers a reciprocating motion to the needle bar lengthwise of its longitudinal axis from a source of driving energy via drive link 58. A counterbalance 60, a crank pin 62, a crank 64, an anchor link 66, and a thread take-up lever 68 of the conventional type are also provided. A thread guide 69 is appended to the side of sewing head 12 and cooperates with thread guide 70 appended to the lower portion of the sewing head to guide the thread to the eye 72 of sewing needle 24. An additional thread guide assembly 74 is attached to theside of the head cover plate 76.

A detailed explanation of the operation of the conventional components set forth above is found in U.S. Pat. No. 2,862,468 granted Dec. 2, 1958 to Ralph E. Johnson.

Push-button 78 is slidably mounted in the head cover plate 76 with the aid of bushing 80, spring 82 and retainer ring 84 and is positioned to cooperate with plunger button 86 preferably at the point of maximum travel height of needle bar 16.

Referring now to FIG. 2 wherein a preferred embodiment of the quick release needle clamp 10 is shown in an exploded view, and to FIG. 3 which is an enlarged perspective view with a quarter section removed to illustrate the cooperation of the parts.

Plunger button 86 in the preferred embodiment is cylindrically shaped with a threaded hole 88 adapted to receive the cylindrically threaded portion 90 of the plunger 92. The middle section 94 and the lower section 95 of the plunger 92 are integrally formed in an elongated rectangular configuration with a retaining finger 96 extending outwardly therefrom in substantially right angle relation relative to the vertical axis of the plunger at the lower portion of the middle section. The retaining finger 96 is inserted in slot 104 and serves to prevent the plunger 92 from both rotating and rising above a predetermined level. The end of the lower section 95 of plunger 92 is formed as a wedge 98, with a forward. surface 100 providing an inclined plane to cooperate with and be in juxtaposition with tapered indent or protrusion 102 formed in sleeve 20 and is the preferred embodiment of cooperatively associated camming means. A needle engaging head provided by the rear surface 106 of wedge 98 remains essentially parallel with the vertical axis of the plunger and comes into intimate contact with a needle inserted through aperture 27 to the height of the roll pin 21 which forms a portion of a needle shank accommodating seat.

A spring 108 rests on abutment 110 provided within the hollow needle bar 16 and continually exerts a force on the lower surface 112 of the plunger button 88 thereby continually urging plunger 92 upwardly until restrained by the upper wall 114 of slot 104 cooperating with retaining finger 96.

The lateral motion clamping action is thereby obtained by the cooperation of indent 102 and surface 100 of the plunger 92. The rear wall 116 of the lower section 95 of plunger 92 is shaped to avoid an interference with roll pin 21 when the plunger is in its upward position. when the plunger is depressed (urged to move downwardly) the inclined portion 118 of rear wall 116 cooperates with roll pin 21 to move the plunger in a lateral direction to unclamp the needle shank 26, and move the wedge 98 an amount sufficient to clear aperture 27 thereby allowing easy removal and insertion of a sewing needle.

The integrally formed lower reduced section 22 of needle bar 16 is disposed concentrically to the vertical axis of the needle bar and is formed with a needle shank receiving slot designated generally by the numeral 120, extending along the vertical or longitudinal axis of section 22 to a point in the needle bar a short distance above the reduced section 22.

Slot 120 includes a further portion of the needle shank accommodating seat which is formed in part at least by a pair of substantially intersecting angularly disposed flat walls 122 and 124, with wall 126 extending parallel to wall 122 and in opposing relationship thereto, wall 124 being alternately referred to as a needle locating surface or rear wall.

A roll pin accepting slot 128 intersects slot 120 at right angles thereto and breaks through the wall of the lower reduced section 22 of the needle-bar l6. Slot 128 cooperates with hole 129 in the sleeve to accept roll pin 21 which retains sleeve 20 to the needle-bar l6.

Grooves 130 and 132 cut in needle bar 16 just above sleeve 20 is used to mount additional attachments which may be used with the sewing machine.

Referring now to FIG. 4 which is an enlarged cross-sectional view of the lower portion of the preferred embodiment of the quick release needle clamp showing the cooperation of the sleeve 20 with the lower end portion 136 of the needle bar 16. Aperture 27 in sleeve 20 is caused to have its circumference tangent with and coinciding with the wall 122 of slot 120. Since the diameter of aperture 27 is larger than the width of slot 120 the wall 126 will reduce the open area of aperture 127 such that it essentially becomes circular in shape with a segment removed.

A needle shank being essentially circular in shape and having a flat thereon may be inserted into the aperture 27 only to the height wherein the needle shank 26 comes into contact with surface 136 of the needle bar. Thereafter the needle shank must be rotated until the flat on the needle shank coincides with the flat wall 126 of the needle shank receiving slot 120 before it can be further inserted into slot 120 to a height determined by roll pin 21. Thus, the proper indexing of the sewing needle is insured when it is inserted into the needle accommodating seat of the needle bar.

Heretofore, has been described a quick release needle clamp which is operable with a minimum of effort and insures proper indexing of the sewing needle.

Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of the invention which is for the purpose of illustration and not to be constructed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope ofthe appended claims.

Having thus set forth the nature of the invention, what 1 claim herein is:

1. A quick release clamping means for securing a sewing machine needle in the free extremity of an endwise reciprocatory sewing machine needle bar, said clamping means comprising a needle accommodating seat in the free extremity of said needle bar including a needle locating surface extending substantially parallel to the path of endwise reciprocation of said needle bar,

a plunger formed with a needle engaging head,

means constraining said plunger for movement relatively to said needle bar substantially parallel to the path of endwise reciprocation thereof and with said needle engaging head disposed opposite said needle locating surface, and

cooperatively associated camming means on said needle bar and on said plunger urging said needle engaging head toward said needle locating surface upon movement of said plunger in one direction along said needle bar and away from said needle locating surface upon movement of said plunger in the other direction along said needle bar.

2. A quick release needle clamping means as set forth in claim 1 including spring means acting between said needle bar and said plunger biasing said plunger in said one direction along said needle bar, and

means accessible to a sewing machine operator for shifting said plunger relatively to said needle bar in a direction opposite to the bias of said spring means.

3. A quick release needle clamping means according to claim 2 wherein said accommodating seat includes indexing means for insuring that said sewing machine needle is inserted in the proper sewing position.

4. A quick release needle clamp for a sewing machine including a hollow cylindrical needle-bar formed with a needle shank accommodating seat having a needle locating surface, comprising a cylindrically shaped sleeve adapted for mounting on said needle-bar, said cylindrically shaped sleeve having a tapered indent extending partially into said needle shank receiving slot, and a spring loaded plunger adapted for slidably mounting within said hollow needle-bar, said plunger having a wedge shaped portion cooperating with said tapered indent of said sleeve continuously urging said plunger toward said needle locating surface providing a clamping relationship therewith.

5. A quick release needle clamp for a sewing machine according to claim 4 further including a spring-loaded pushbutton cooperating with said spring-loaded plunger to activate said plunger for inserting and releasing a sewing needle.

6. A quick release needle clamp for a sewing machine according to claim 4 wherein said cylindrically shaped sleeve includes a circular aperture adapted for inserting a sewing needle therethrough, said needle having a round shank with an indexing flat thereon, the circumference of said aperture being tangent to one wall of said needle shank receiving slot whereby said needle is properly indexed for sewing when inserted in said needle shank receiving slot.

7. A quick release needle clamp for a sewing machine according to claim 4 wherein said tapered indent is provided by an appendage affixed to said sleeve.

8. A quick release needle clamp for a sewing machine including a hollow cylindrical needle-bar formed with a needle shank receiving slot, comprising a cylindrically shaped sleeve, having an internal protrusion, affixed to said needle-bar, one end of said sleeve being adapted for accepting a sewing needle therethrough, and a spring loaded plunger adapted for slidably mounting within said hollow needle-bar said plunger having a portion thereon adapted for cooperation with said internal protrusion of said sleeve continuously urging said plunger toward the rear wall of said needle shank receiving slot providing a clamping relationship with said needle-bar.

9. A quick release needle clamp for a sewing machine according to claim 8 further including a spring-loaded push-button cooperating with said spring loaded plunger to activate said plunger for inserting and releasing said sewing needle.

* i i t 

1. A quick release clamping means for securing a sewing machine needle in the free extremity of an endwise reciprocatory sewing machine needle bar, said clamping means comprising a needle accommodating seat in the free extremity of said needle bar including a needle locating surface extending substantially parallel to the path of endwise reciprocation of said needle bar, a plunger formed with a needle engaging head, means constraining said plunger for movement relatively to said needle bar substantially parallel to the path of endwise reciprocation thereof and with said needle engaging head disposed opposite said needle locating surface, and cooperatively associated camming means on said needle bar and on said plunger urging said needle engaging head toward said needle locating surface upon movement of said plunger in one direction along said needle bar and away from said needle locating surface upon movement of said plunger in the other direction along said needle bar.
 2. A quick release needle clamping means as set forth in claim 1 including spring means acting between said needle bar and said plunger biasing said plunger in said one direction along said needle bar, and means accessible to a sewing machine operator for shifting said plunger relatively to said needle bar in a direction opposite to the bias of said spring means.
 3. A quick release needle clamping means according to claim 2 wherein said accommodating seat includes indexing means for insuring that said sewing machine needle is inserted in the proper sewing position.
 4. A quick release needle clamp for a sewing machine including a hollow cylindrical needle-bar formed with a needle shank accommodating seat having a needle locating surface, comprising a cylindrically shaped sleeve adapted for mounting on said needle-bar, said cylindrically shaped sleeve having a tapered indent extending partially into said needle shank receiving slot, and a spring loaded plunger adapted for slidably mounting within said hollow needle-bar, said plunger having a wedge shaped portion cooperating with said tapered indent of said sleeve continuously urging said plunger toward said needle locating surface providing a clamping relationship therewith.
 5. A quick release needle clamp for a sewing machine according to claim 4 further including a spring-loaded pushbutton cooperating with said spring-loaded plunger to activate said plunger for inserting and releasing a sewing needle.
 6. A quick release needle clamp for a sewing machine according to claim 4 wherein said cylindrically shaped sleeve includes a circular aperture adapted for inserting a sewing needle therethrough, said needle having a round shank with an indexing flat thereon, the circumference of said aperture being tangent to one waLl of said needle shank receiving slot whereby said needle is properly indexed for sewing when inserted in said needle shank receiving slot.
 7. A quick release needle clamp for a sewing machine according to claim 4 wherein said tapered indent is provided by an appendage affixed to said sleeve.
 8. A quick release needle clamp for a sewing machine including a hollow cylindrical needle-bar formed with a needle shank receiving slot, comprising a cylindrically shaped sleeve, having an internal protrusion, affixed to said needle-bar, one end of said sleeve being adapted for accepting a sewing needle therethrough, and a spring loaded plunger adapted for slidably mounting within said hollow needle-bar said plunger having a portion thereon adapted for cooperation with said internal protrusion of said sleeve continuously urging said plunger toward the rear wall of said needle shank receiving slot providing a clamping relationship with said needle-bar.
 9. A quick release needle clamp for a sewing machine according to claim 8 further including a spring-loaded push-button cooperating with said spring loaded plunger to activate said plunger for inserting and releasing said sewing needle. 